The transaction is expected to be completed in the third quarter.
Based in Salt Lake City, Goal Zero markets a suite of portable solar power and battery-pack products and accessories and employs 100 people.
Goal Zero was originally established to deliver power systems in remote areas of developing nations that have poor access to electricity.
NRG plans to add Goal Zero to its NRG Home end-use energy consumer strategy that envisages cross-selling opportunities between system power, residential solar and personal power.
The acquisition is part NRG’s plans to provide sustainable solutions to end-use energy consumers in the US.
NRG Energy president and CEO David Crane said: "The acquisition of Goal Zero – the best company in its field – aligned alongside our established system power franchise and our fast-growing residential solar business, dramatically expands our reach, enabling us to serve every American who desires to be part of the clean energy future."
Goal Zero founder and CEO Robert Workman said: "Our mission is to put reliable power in the hands of every human on earth.
"Being part of NRG allows us to reach this goal in a much more powerful way."
